Question

5 и 7 номера пожалуйста

Answer 1

5. а)
$8x + 4 = 5x - 20 \\ 8x - 5x = - 20 - 4 \\ 3x = - 24 \\ x = - 24 \div 3 \\ x = - 8$
б)

$2y = 7y + 10 \\ 2y - 7y = 10 \\ - 5y = 10 \\ y = 10 \div ( - 5) \\ y = - 2$
в)

$x + 6 - 8 = 2x \\ x - 2 = 2x \\ x - 2x = 2 \\ - x = 2 \\ x = - 2$
г)

$- 5y + 13 - 6 = - y - 1 \\ - 5y + 7 = - y - 1 \\ - 5y + y = - 1 - 7 \\ - 4y = - 8 \\ y = - 8 \div ( - 4) \\ y = 2$
7. а)

$2x - 6 = 14 \\ 2x = 14 + 6 \\ 2x = 20 \\ x = 20 \div 2 \\ x = 10$
б)
$9 - 3x = 0 \\ - 3x = - 9 \\ x = - 9 \div ( - 3) \\ x = 3$
в)
$- 15 - x = 7 \\ - x = 7 + 15 \\ - x = 22 \\ x = - 22$
г)

$4x - 2 = 5x - 9 \\ 4x - 5x = - 9 + 2 \\ - x = - 7 \\ = 7$
д)

$x - 9 = - 4x - 7 \\ x + 4x = - 7 + 9 \\ 5x = 2 \\ x = 2 \div 5 \\ x = 0.4$
е)

$0.6 - 7x= 8 - 6x \\ - 7x + 6x = 8 - 0.6 \\ - x = 7.4 \\ x = - 7.4$